The mineral manaksite, KNaMnSi4O10, as a supercapattery-type electrochemical energy storage material

The manaksite mineral KNaMnSi4O10 was synthesized and used to fabricate electrodes, which were investigated for electrochemical energy storage (EES) application using cyclic voltammetry (CV), galvanostatic charge and discharge (GCD), and electrochemical impedance spectroscopy (EIS). Optimum weight percentages (wt%) of electrode components were established as 10 wt% polytetrafluoroethylene (PTFE) binder, 15 wt% RuO2 and 5 wt% carbon black. RuO2 was added to improve electrical conductivity. A ratio of 13 : 3 for KNaMnSi4O10 : RuO2 was used in the fabrication of the electrode. A study of the suitable electrolyte and corresponding concentration to use was done using NaOH and KOH, both at concentrations of 1 M, 3 M and 6 M, with 3 M NaOH as the optimum electrolyte and concentration. The KNaMnSi4O10 yielded a specific capacity of 106 mA h g-1. An investigation into the energy storage mechanism from a plot of log I(ν) vs. log ν, where I is current and ν is the scan rate gave a b value parameter of 0.8; that is, in-between 0.5 obtained for a pure battery material and 1.0 for a pure capacitor material. Accordingly, KNaMnSi4O10 exhibited a battery-supercapacitor duality phenomenon consistent with supercapattery materials. The KNaMnSi4O10 electrochemical system involved both capacitive and diffusion-controlled processes and was found to have good cyclic stability. It is concluded that KNaMnSi4O10 is a potential electrochemical energy storage material.

A CaCuSi4O10/GCE electrochemical sensor for detection of norfloxacin in pharmaceutical formulations

This study reports on a calcium copper tetrasilicate (CaCuSi₄O₁₀)/glassy carbon electrode (GCE) electrochemical sensor developed for rapid sensing and quantification of an antibacterial drug, norfloxacin, using both cyclic voltammetry and differential pulse voltammetry. The sensor was fabricated by modifying a glassy carbon electrode with the CaCuSi₄O₁₀. Electrochemical impedance spectroscopy was performed and the Nyquist plot showed that the CaCuSi₄O₁₀/GCE had a lower charge transfer resistance of 22.1 Ω cm² compared to the GCE with a charge transfer resistance of 43.5 Ω cm². Differential pulse voltammetry showed that the optimum pH for the electrochemical detection of norfloxacin in potassium phosphate buffer solution (PBS) electrolyte was pH 4.5 and an irreversible oxidative peak was found at 1.067 V. Two linear ranges were established at 0.01 to 0.55 μM and 0.55 μM to 82.1 μM, and the limit of detection was ca. 0.0046 μM. We further demonstrated that the electrochemical oxidation was controlled by both diffusion and adsorption processes. The sensor was investigated in the presence of interferents and was found to be selective toward norfloxacin. The pharmaceutical drug analysis was done to establish method reliability and a significantly low standard deviation of 2.3% was achieved. The results suggest that the sensor can be applied in the detection of norfloxacin.

In situ polymerization and electrical conductivity of polypyrrole/cellulose nanocomposites using Schweizer's reagent

Cellulose-based composites have attracted interest given the shift towards 'green' materials, but achieving uniform dispersions of cellulose in polymer matrices and/or enhancement of interfacial interactions between components remains challenging. Herein we report the preparation of polypyrrole/cellulose nanocomposites in [Cu(NH₃)₄(H₂O)₂](OH)₂ (Schweizer's reagent/cuoxam)-based reaction media via in situ polymerization. The effect of cellulose template morphology and reaction media on the microstructure, electrical conductivity, and surface wettability was studied. Aqueous reaction media favored the formation of a uniform polypyrrole coating encapsulating the cellulose fibers; concentrated cuoxam solutions promoted inhomogeneity and exhibited a progressive decline in conductivity. The maximum conductivity attained was 3.08 S cm^-1 from a bacterial cellulose-templated composite prepared in aqueous reaction media and afforded an approximately threefold increase in conductivity when compared with pure PPy at 1.14 S cm^-1. Generally, the composites resembled wetting surfaces - with highly concentrated cuoxam solutions yielding improved hydrophilicity, while substitution of bacterial cellulose with nanocrystalline cellulose engendered a shift towards hydrophobicity. Most composites displayed a contact angle of less than 90° suggesting PPy/cellulose composites tended towards hydrophilic behavior. This study highlights investigations into the viability of cellulose solvents as a facile means to control the structure and performance of in situ functionalized cellulose nanocomposites.

Interstitial hydrides in nanoclusters can reduce M(I) (M = Cu, Ag, Au) to M(0) and form stable superatoms

High-nuclearity clusters resemble the closest model between the determination of atomically precise chemical species and the bulk metallic version thereof, and both impacts on a variety of applications, including catalysis, optics, sensors, and new energy sources.  Our interest lies with the nanoclusters of the Group 11 (Cu, Ag, Au) metals stabilized by dichalcogenido and hydrido ligands.  Herein, we describe superatoms formed by the clusters and their relationship with precursor hydrido clusters.  Specifically, our concept seeks to demonstrate a possible correlation that exist between hydrido clusters (and nanoalloys) and the formation of superatoms, with the loss of hydrides and typically with release of H 2 gas.  These reactions appear to be internal self-redox reactions and require no additional reducing agent, but does seem to require a similar core structure.  Knowledge of such processes could provide insight into how clusters grow and an understanding in bridging the atomically precise cluster - metal nanoparticle mechanism.

Synergistically enhanced performance of transition-metal doped Ni2P for supercapacitance and overall water splitting

Cost-effective and readily available catalysts applicable for electrochemical conversion technologies are highly desired. Herein, we report the synthesis of dithiophosphonate complexes of the type [Ni{S₂P(OH)(4-CH₃OC₆H₄)}₂] (1), [Co{S₂P(OC₄H₉)(4-CH₃OC₆H₄)}₃] (2) and [Fe{S₂P(OH)(4-CH₃OC₆H₄)}₃] (3) and employed them to prepare Ni₂P, Co-Ni₂P and Fe-Ni₂P nanoparticles. Ni₂P was formed by a facile hot injection method by decomposing complex 1 in tri-octylphosphine oxide/tri-n-octylphosphine at 300 °C. The prepared Ni₂P was doped with Co and Fe employing complexes 2 and 3, respectively, under similar experimental conditions. Doping Ni₂P with Co and Fe demonstrated synergistic improvement of Ni₂P performance as an electrocatalyst in supercapcitance, hydrogen evololution and oxygen evolution reactions in alkaline medium. Cobalt doping improved the Ni₂P charge storage capacity with a supercapacitance of 864 F g^-1 at 1 A g^-1 current density. Fe doped Ni₂P recorded the lowest overpotential of 259 mV to achieve a current density of 10 mA cm^-2 and a Tafel slope of 80 mV dec^-1 for OER, better than the undoped Ni₂P and the benchmark IrO₂. Likewise, Fe-doped Ni₂P electrode required the lowest overpotential of 68 mV with a Tafel slope of 110 mV dec^-1 to attain the same current density for HER. All catalysts showed excellent stability in supercapacitance and overall water splitting reactions, indicating their practical use in energy conversion technologies.

Crystal structure of (morpholine-1-carbodithioato-κ2-S,S′)bis(triphenylphosphine-κ-P)gold(I), C41H38AuNOP2S2

C41H38AuNOP2S2, triclinic, P 1 ‾ $‾{1}$ (no. 2), a = 10.0821(2) Å, b = 12.9409(2) Å, c = 14.7183(3) Å, α = 76.207(1)°, β = 80.444(1)°, γ = 75.592(1)°, V = 1794.63(6) Å3, Z = 2, R gt (F) = 0.0170, wR ref (F 2) = 0.0407, T = 150 K.

Triphenylphosphine-Assisted Transformation of NiS to Ni2P through a Solvent-Less Pyrolysis Route: Synthesis and Electrocatalytic Performance

Straightforward synthetic routes to the preparation of transition metal phosphides or their chalcogenide analogues are highly desired due to their widespread applications, including catalysis. We report a facile and simple route for the preparation of a pure phase nickel phosphide (Ni₂P) and phase transformations in the nickel sulfide (NiS) system through a solvent-less synthetic protocol. Decomposition of different sulfur-based complexes (dithiocarbamate, xanthate, and dithiophosphonate) of nickel(II) was investigated in the presence and absence of triphenylphosphine (TPP). The optimization of reaction parameters (nature of precursor, ratio of TPP, temperature, and time) indicated that phosphorus- and sulfur-containing inorganic dithiophosphonate complexes and TPP (1:1 mole ratio) produced pure nickel phosphide, whereas different phases of nickel sulfide were obtained from dithiocarbamate and xanthate precursors in the presence or absence of TPP. A plausible explanation of the sulfide or phosphide phase formation is suggested, and the performance of Ni₂P was investigated as an electrocatalyst for supercapacitance and overall water-splitting reactions. The performance of Ni₂P with the surface free of any capping agents is not well explored, as common synthetic methods are solution-based routes; therefore, the electrocatalytic performance was also compared with metal phosphides, prepared by other routes. The highest specific capacitance of 367 F/g was observed at 1 A/g, and the maximum energy and power density of Ni₂P were calculated to be 17.9 Wh/kg and 6951 W/kg, respectively. The prepared nickel phosphide required overpotentials of 174 and 316 mV along with Tafel slopes of 115 and 95 mV/dec to achieve a current density of 10 mA/cm² for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively.

[Cu{SC(O)OiPr}]96: A Giant Self-Assembled Copper(I) Supramolecular Wheel Exhibiting Photoluminescence Tuning and Correlations with Dynamic Solvation and Solventless Synthesis

The hierarchical self-organization of structurally complex high-nuclearity metal clusters with metallosupramolecular wheel architectures that are obtained from the self-assembly of smaller solvated cluster units is rare and unique. Here, we use the potentially heteroditopic monothiocarbonate ligand and demonstrate for the first time the synthesis and structure of a solvated non-cyclic hexadecanuclear cluster [Cu{SC(O)OⁱPr}]₁₆·2THF (1) that can simultaneously desolvate and self-assemble in solution and subsequently form a giant metallaring, [Cu{SC(O)OⁱPr}]₉₆ (2). We also demonstrate a luminescent precursor to cluster (2) can be achieved through a solventless and rapid mechanochemical synthesis. Cluster (2) is the highest nuclearity copper(I) wheel and the largest metal cluster containing a heterodichalcogen (O, S) ligand reported to date. Cluster (2) also exhibits solid-state luminescence with relatively long emission lifetimes at 4.1, 13.9 (μs). The synthetic strategy described here opens new research avenues by replacing solvent molecules in stable {Cu₁₆} clusters with designed building units that can form new hybrid and multifunctional finite supramolecular materials. This finding may lead to the development of novel high-nuclearity materials self-assembled in a facile manner with tunable optical properties.

Degradation of o-Chloranil Using Nanocrystalline-Cellulose/TiO2 Composites via a Solar Photocatalytic Route

ABSTRACT Water pollution by organic pollutants is a continuous and increasing problem of global concern. In this paper, we developed a nanocrystalline cellulose (NCC) and titania (TiO2) based nanocomposite for the photocatalytic degradation of o-chloranil via aqueous wet impregnation. Different NCC loadings (10, 20, 40, and 80%) were used, and several analytical and microscopy techniques characterised the NCC/TiO2 catalyst. The efficiency of TiO2 as a photo-catalyst was enhanced through the chiral nematic nature and potential charge carrier capacity of NCC, which lowered the rate of electron recombination. The NCC/TiO2 material was used in the solar-driven photo-degradation of o-chloranil (3,4,5,6-tetrachloro-1,2-benzoquinone), a by-product of a commonly used pesticide. The successful decomposition of o-chloranil led to the successful identification of three breakdown products, namely 2,3-dichloro-4,5-dioxohex-2-enedoic acid (DCA), 2,3-dioxosuccinic acid (DSA) and oxalic acid (OA). The 20% NCC/TiO2 catalyst was found to be optimum and showed excellent degradation and mineralisation of o-chloranil within 2 hours (~90% degradation after 2 hours or 0.00920 mols of the total 0.0102 mols). The degradation products were analysed and identified using GC-MS. The photo-catalyst offers many benefits, including ease of preparation, a low cost-factor, and high stability with no loss of activity. Keywords: nanocrystalline cellulose; o-chloroanil; photocatalyst; photo-degradation; titania

A construction guide for high-nuclearity (≥50 metal atoms) coinage metal clusters at the nanoscale: bridging molecular precise constructs with the bulk material phase

Synthesis remains a major strength in chemistry and materials science and relies on the formation of new molecules and diverse forms of matter. The construction and identification of large molecules poses specific challenges and has historically lain in the realm of biological (organic)-type molecules with evolved synthesis methods to support such endeavours. But with the development of analytical tools such as X-ray crystallography, new synthesis methods toward large metal-based (inorganic) molecules and clusters have come to the fore, making it possible to accurately determine the precise distribution of hundreds of atoms in large clusters. In this review, we focus on different synthesis protocols used to form new metal clusters such as templating, alloying and size-focusing strategies. A specific focus is on group 11 metals (Cu, Ag, Au) as they currently predominate large metal cluster investigations and related Au and Ag bulk surface phenomena. This review focuses on metal clusters that have very high-nuclearity, i.e. with 50 or more metal centers within the isolated cluster. This size domain, it is believed, will become increasingly important for a variety of applications as these metal clusters are positioned at the interface between the molecular and bulk phases, whilst remaining a classic nanomaterial and retaining unique nano-sized properties.

Synthesis and structures of divalent Co, Ni, Zn and Cd complexes of mixed dichalcogen and dipnictogen ligands with corrosion inhibition properties: experimental and computational studies

The structural and corrosion inhibition properties of four different transition-metal complexes of heteroleptic S-donor atom dithiophosphonate and N-donor atom phenanthroline ligands are reported. Full structural characterization of the Co, Ni, Zn and Cd complexes was achieved with the aid of single-crystal X-ray crystallography. Structural elucidation revealed the formation of a 4-coordinate Zn(ii) complex, and 6-coordinate Ni(ii) and Cd(ii), as well as a novel dithiophosphonato Co(ii) complex. The ability of the complexes with this ligand type to act as inhibitors of mild steel corrosion in 1 M HCl solution is reported for the first time. Corrosion inhibition potentials of the complexes were assessed using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and density functional theory (DFT). The open circuit potential (OCP) time profile showed the system achieved a steady-state potential before the first 600 s after submerging the working electrode in the corrosive medium. The studied metal complexes are good inhibitors of mild steel corrosion in 1 M HCl and were found to retard the corrosion rate by forming an adsorbed pseudocapacitive film on the steel surface. The order of inhibition efficiencies was in the order Ni (94.14%) > Cd (92.28%) > Zn (91.14%) > Co (72.53%).

Formation of dialysis-free Kombucha-based bacterial nanocellulose embedded in a polypyrrole/PVA composite for bulk conductivity measurements

The preparation of dialysis-free bacterial nanocrystalline cellulose (BNCC) combined with a suitable polymer to form a robust conducting material remains a challenge. In this work, we developed a polypyrrole@BNCC/PVA nanocomposite that avoids the time-consuming dialysis step and which exhibits bulk electrical conductivity. The nanocellulose (NC) was derived from bacterial cellulose (BC) that was grown from a symbiotic colony of bacteria and yeast (SCOBY) starting from Kombucha tea, and then subjected to sulfuric acid hydrolysis that led to isolable bacterial nanocrystalline cellulose (BNCC) product and subsequently utilized as a stabilizer and support. Pyrrole monomer was reacted with FeCl₃·6H₂O as a polymerization initiator to form polypyrrole (PPy) and combined with BNCC it produced PPy@BNCC nanocomposite. We found PPy to BNCC in a 1 : 1 ratio provided the best suspension of the components and formed a well dispersed homogeneous network. The PPy@BNCC nanocomposite was then suspended in polyvinyl alcohol (PVA), that facilitated the construction of a continuous PPy@BNCC/PVA conductive network in the matrix. We designed an in-house electrical measurement apparatus and developed a method that recorded bulk resistance. The results obtained from the measurements of the electrical properties of the PPy@BNCC/PVA composite prepared dialysis-free were then compared with (i) a dialyzed sample of similar composition, and (ii) a traditional four-point probe measurement. The PPy@BNCC/PVA dialysis-free sample showed a higher conductivity compared to the dialyzed composite at 4.27 × 10^-1 and 3.41 × 10^-1 S m^-1, respectively, and both values closely matched the traditional four-point probe measurement.

Retraction: Synthesis of triazolidine-3-one derivatives through the nanocellulose/hydroxyapatite-catalyzed reaction of aldehydes and semicarbazide

Retraction of ‘Synthesis of triazolidine-3-one derivatives through the nanocellulose/hydroxyapatite-catalyzed reaction of aldehydes and semicarbazide’ by Vashen Moodley et al., New J. Chem., 2017, 41, 6455–6463, DOI: 10.1039/c7nj00855d.

Four-Component Fusion Protocol with NiO/ZrO2 as a Robust Recyclable Catalyst for Novel 1,4-Dihydropyridines

Nickel oxide loaded on zirconia (NiO/ZrO₂) as an expedient catalyst is reported for the synthesis of 18 unsymmetrical 1,4-dihydropyridine derivatives. The Lewis acidic nature of the catalyst proved an excellent choice for the one-pot, four-component fusion reaction with excellent yields of 89-98% and a completion time of 20-45 min. Mechanistic studies show that enamine and imine functionalities are the two possible pathways for the formation of 1,4-dihydropyridines with high selectivity. Crystal structures of two novel compounds (5a, 5c) were reported. The catalyst demonstrated reusability up to six cycles. The reaction at room temperature and ethanol as a solvent make this protocol green and economical.

Copper hydride clusters in energy storage and conversion

Copper hydride clusters of variable nuclearity are derived from hydrogen and HCOOH as emerging energy storage materials and models.

Ag₂O on ZrO₂ as a Recyclable Catalyst for Multicomponent Synthesis of Indenopyrimidine Derivatives

We describe the synthesis of silver loaded on zirconia and its use as an efficient catalyst for a one-pot three-component reaction to synthesize 11 indenopyrimidine derivatives, of which 7 are new compounds. The procedure involves substituted benzaldehydes, indane-1,3-dione, and guanidinium hydrochloride, with ethanol as solvent. The proposed green protocol at room temperature is simple and efficient, giving excellent yields (90⁻96%) in short reaction times (<30 min). The protocol works well according to the green chemistry principles with respect to high atom economy, no need for column separation, and reusability of the catalyst, which are attractive features. XRD, TEM, SEM, and BET analysis were used to characterize the catalyst materials.

An efficient and green approach for the synthesis of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates using Bi2O3/ZrO2 as a reusable catalyst

A novel material of bismuth loaded on zirconia (Bi₂O₃/ZrO₂) is synthesized by simple wet-impregnation method and characterized by several techniques (P-XRD, TEM, SEM, BET, etc.). Bi₂O₃/ZrO₂ proved to be a good catalyst for the four-component, one-pot reaction to produce a new series of 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylate derivatives with excellent yields (91 to 98%) under mild conditions at RT with short reaction times (≈20 min). The structures of the target molecules were confirmed by ¹H NMR, ¹³C NMR, ¹⁵N NMR, HRMS and FT-IR. The catalyst is easily separable and can be reused for six cycles without ostensible loss of activity. This method is inexpensive, atom-efficient and no chromatographic separations are needed.

Novel bismuth loaded on zirconia (Bi₂O₃/ZrO₂) as a reusable catalyst to synthesize 2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates under mild conditions.

Nanocrystalline cellulose isolated from discarded cigarette filters

We report the isolation of nanocrystalline cellulose (NCC) produced from discarded cigarette filters (DCF). The DCF were processed into cellulose via ethanolic extraction, hypochlorite bleaching, alkaline deacetylation, and then converted into NCC by sulfuric acid hydrolysis. The morphological structures of the isolated NCC established with TEM showed that the nanocrystals were needle-like with a mean length of 143nm. FEGSEM showed the morphological transition of the micro-sized DCF to self-assembled NCC while EDX revealed the presence of Ti (as TiO₂) in DCF, which was retained in the NCC. A NCC sample was freeze-dried and showed a specific surface area of 7.78m²/g. The crystallinity of the NCC film and freeze-dried samples were 96.77% and 94.47%, respectively. Crystallite sizes of the freeze-dried (8.4nm) and film (7.6nm) samples correlated with the mean width (8.3nm) of the NCC observed under TEM.

Retracted Article: Synthesis of triazolidine-3-one derivatives through the nanocellulose/hydroxyapatite-catalyzed reaction of aldehydes and semicarbazide

First use of the nanocellulose/hydroxyapatite heterogeneous catalyst to produce triazolidine-3-one derivatives from aldehydes and semicarbazide.

Polyhydrido Copper Clusters: Synthetic Advances, Structural Diversity, and Nanocluster-to-Nanoparticle Conversion

Metal hydride clusters have historically been studied to unravel their aesthetically pleasing molecular structures and interesting properties, especially toward hydrogen related applications. Central to this work is the hydride ligand, H¯, the smallest closed-shell spherical anion known. Two new developments in polyhydrido nanocluster chemistry include the determination of heretofore unknown hydride coordination modes and novel structural constructs, and conversion from the molecular entities to rhombus-shaped copper nanoparticles (CuNPs). These advances, together with hydrogen evolution and catalysis, have provided both experimentalists and theorists with a rich scientific directive to further explore. The isolation of hexameric [{(Ph3P)CuH}6] (Stryker reagent) could be regarded as the springboard for the recent emergence of polyhydrido copper cluster chemistry due to its utilization in a variety of organic chemical transformations. The stability of clusters of various nuclearity was improved through phosphine, pyridine, and carbene type ligands. Our focus lies with the isolation of novel copper (poly)hydride clusters using mostly the phosphor-1,1-dithiolato type ligands. We found such chalcogen-stabilized clusters to be exceptionally air and moisture stable over a wide range of nuclearities (Cu7 to Cu32). In this Account, we (i) report on state-of-the-art copper hydride cluster chemistry, especially with regards to the diverse and novel structural types generally, and newly discovered hydride coordination modes in particular, (ii) demonstrate the indispensable power of neutron diffraction for the unambiguous assignment and location of hydride ligand(s) within a cluster, and (iii) prove unique transformations that can occur not only between well characterized high nuclearity clusters, but also how such clusters can transform to uniquely shaped nanoparticles of several nanometers in diameter through copper hydride reduction. The increase in the number of low- to high-nuclearity hydride clusters allows for different means by which they can be classified. We chose a classification based on the coordination mode of hydride ligand within the cluster. This includes copper clusters associated with bridging (μ2-H) and capping (μ3-H) hydride modes, followed by an interstitial (μ4-H) hydride mode that was introduced for the first time into octa- and hepta-nuclear copper clusters stabilized by dichalcogen-type ligands. This breakthrough provided a means to explore higher nuclearity polyhydrido nanoclusters, which contain both capping (μ3-H) and interstitial (μ(4-6)-H) hydrides. The presence of bidentate ligands having mixed S/P dative sites led to air- and moisture-stable copper hydride nanoclusters. The formation of rhombus-shaped nanoparticles (CuNPs) from copper polyhydrides in the presence of excess borohydrides suggests the presence of metal hydrides as intermediates during the formation of nanoparticles.

Ceria-Vanadia/Silica-Catalyzed Cascade for C-C and C-O Bond Activation: Green One-Pot Synthesis of 2-Amino-3-cyano-4H-pyrans

We designed a ceria-vanadia/silica (Ce-V/SiO2) heterogeneous catalyst and used it for the green and efficient synthesis of 2-amino-3-cyano-4H-pyran derivatives. The green reaction was a multicomponent one-pot condensation of 5,5-dimethylcyclohexane-1,3-dione, aromatic aldehyde, and malononitrile in an eco-compatible solvent (ethanol). The catalyst was synthesized and fully characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. The reported procedure offers a number of advantages including decreased reaction times, mild conditions, high yields, operational simplicity, and environmentally benign and simple work-up procedures. Furthermore, the catalyst is economical, fully recyclable, and reusable for over five runs while preserving its high activity. The synthesized 2-amino-3-cyano-4H-pyran products can later be used for pharmaceutical purposes.

Mn doped ZrO2 as a green, efficient and reusable heterogeneous catalyst for the multicomponent synthesis of pyrano[2,3-d]-pyrimidine derivatives

A simple and an efficient method has been developed for the one-pot multicomponent synthesis of pyrano[2,3-d]-pyrimidine derivatives.

Anion templating from a silver(i) dithiophosphate 1D polymer forming discrete cationic and neutral octa- and decanuclear silver(i) clusters

The polymer [Ag₅{S₂P(OⁱPr)₂}₄]_n(PF₆)_n forms discrete Ag₈ and Ag₁₀ clusters with encapsulated anions; the nuclearity depends on the M : L stoichiometric control.